For the synchronisation to work between Zoho CRM and Zoho Inventory it is mandatory that your Zoho Products and Zoho Inventory Sync is working and that the Zoho CRM Products [Product Code] and Zoho Inventory [Item SKU's] are identical.  

IT IS ALSO IMPORTANT TO NOTE THAT ZOHO INVENTORY WILL ONLY SYNC ON A 2 HOUR BASIS AND SOMETIMES CHANGES DO NOT REFELECT FOR A FEW HOURS AFTER THAT.  OUR SUGGESTION IS THAT YOU CREATE ITEMS WITHIN ZOHO INVENTORY FIRST AND THEN WHEN THEY APPEAR IN ZOHO CRM ADD THEM THEN TO YOUR B2B ACCOUNTS (THAT IS DON'T CREATE PRODUCTS IN ZOHO CRM).   YOU CAN ALSO PERFORM AN INSTANT SYNC FROM ZOHO INVENTORY BUT EVEN THIS TAKES SOMETIME TO COMPLETE.